False advertising

On the 24 July 2022 I went to The Fix store at City View shopping center in Durban.I noticed a sign that says sale and you buy 2 items and get 2 free. I then chose 4 items from the area where they had such sign. I made payment using my Exact store card. When I reached home I went through the receipt and immediately noticed that I had paid for all four items and actually there was no free items. I was charged as per the sale irrespective of the number of items purchased. I then went to the store on the 25 July and I spoke to Zanele and Wendy, I wasn't satisfied with their explanation. I explained to them that according to my understanding on a buy 2 get 2 sale I should be only paying for the most expensive items and get cheaper ones free and those items should display 'minus' on my receipt.